The correct answer is option 'B' HTTP.

HTTP stands for Hypertext Transfer Protocol, which is used for browsing websites. It is an application layer protocol that allows communication between web servers and web clients.

HTTP works on top of the TCP protocol, which provides reliable transmission of data across the network. When a user requests a web page, the web browser sends an HTTP request to the web server, which then sends an HTTP response containing the requested web page.

The HTTP protocol is based on a client-server model, where the client (web browser) sends requests to the server, and the server responds with the requested data. The protocol is stateless, which means that each request/response message is independent of any previous or subsequent messages.

HTTP uses various methods (GET, POST, PUT, DELETE, etc.) to request or submit data to the server. It also supports various status codes (200, 404, 500, etc.) to indicate the success or failure of a request.

In summary, HTTP is the protocol used for browsing websites, and it allows web browsers to communicate with web servers to request and receive web pages.